Arc-lamp electrode.



J. H. HALLBERG.

ARC LAMP ELECTRODE.

APPLICATION FILED APR. 26, 1907.

Patented May 24, 1910.

36 I t 14:36:, jg tzven 0r W g 5% JQAMM by JWQ 5? Zj one of theelectrodes UNITED STATES PATENT OFFICE.

JOSEF H. HALLBERG, OF NEW YORK, N. Y., ASSIGNOR TO THE BECK FLAMING LAMPCOMPANY, OF CANTON, NEW YORK, A CORPORATION OF NEW YORK.

ARC-LAM]? ELECTRODE.

Patented May 24, 1910. Serial No. 370,348.

To all whom it may concern:

Be it known that I, J osnr H. HALLBERG, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented certain new and useful Improvements in Arc-LampElectrodes, of which the following is a specification.

My invention relates to electric arc lamps and particularly to certainimprovements in the electrodes thereof of that type embodying a rib toengage a support.

In lamps of this character, in which the electrodes to be burned arecomposed of columns of material of different degrees of fusibility,there results at times an unsteadiness of the light due to the movementof the arc with respect to the longitudinal center of the electrodebecause of the fact that the arc will leave the core of the electrode,or the place where the more fusible salts are located, and movingelsewhere will vary the resistance and make the light unsteady. Thetendency of the arc is to move to the point of lowest resistance and thepurpose of my invention is so to locate this point with respect to thefusible core that a practically uniform consumption of the electrodewill result. I accomplish this by furnishing the electrode with ametallic conductor embedded either in the rib or in the body of theelectrode between the core and the rib. The arc naturally seeks thepoint of least resistance which is, of course, the lower terminal of themetallic conductor. This brings the arc to a point where the flame isalways in contact with the body of the electrode near the core andcauses a substantially uniform consumption of the entire electrode,because the indirect heat of the arc assists in the consumption of theelectrode around the metallic conductor. I also provide the rib of theelectrode with serrations along its rear edge. As each one of the teethis consumed the electrode at once drops so that the next tooth above isbrought to rest upon the support.

In the drawings, Figure l is a central vertical section and partialelevation of the lower part of an arc lamp embodying of my invention,the other electrode not being shown; Fig. 2 is an enlarged detail of thelower end of the electrode and its support; Fig. 3 is a section on theplane of the line 3-3 in Fig. 2; and Fig. 4 is a transverse sectionthrough the form of electrode in which the is embedded in the rib.

In the drawings 2 is a base preferably cylindrical in form and suitablysupported.

66 is a transverse apertured plate of nonconducting material adapted torest in its lowermost position upon a shoulder 65 around the inner wallof the base 2.

Hangers 6 are suitably supported from the upper part of the lamp andterminate at the bottom in sleeves 8 adapted to support and encircle theelectrodes which move through them. The sleeves 8 pass through suitableapertures 670 in the plate 66 and are each provided with brackets 48 tothe lower extremities of which are secured conical permanent supports 50upon which the ribs of the electrodes rest.

Each electrode comprises a body a made of carbon in the usual manner andpreferably cylindrical or polyhedral in form. At or near the central ofthe body is a core 6 made of suitable fusible salts of the alkalinemetals in a manner well known to the art. At the rear of the body a andpreferably made integral with it, and made of the same material as thebody a is a longitudinal rib c and longitudinally arranged either withinthe rib or in the body a between the rib and the core Z) is a metallicconductor a in the form of a wire.

The rear edge of the rib c is preferably provided with teeth 6 arrangedin series and presenting the appearance of a saw edge. The angle of thelower edges of the teeth should be substantially the same as the angleof the edge of the permanent support 50 with the horizon, so as toafford as much supporting surface to the rib as possible.

The mode of operation of my improved electrode is readily understood.When the lamp is energized and the arc is formed it seeks the wire (Zand draws the flame across the body of the carbon 64 and past the lowerextremity of the core 5. It also assists in the combustion of the rib c,by its indirect heat. As one of the teeth e burns away and finallycrumbles the electrode drops until the next tooth above rests upon thesupport 50.

The electrode herein described and claimed is well adapted for use in alamp of the construction exemplified by the application for UnitedStates patent which was filed by me March 9, 1907 and is numbered,serially, 361365.

What I claim as new is 1. An electrode for are lamps, comprising a bodyof carbon having a core, a radially projecting external rib, and alongitudinal conductor arranged in the electrode in a plane which isapproximately between the core and the outer surface of the rib.

2. A cored electrode for arc lamps, having an external longitudinallyextending rib and provided with a longitudinal metallic conductor whichis arranged in the electrode in substantially the same radial plane asthe rib.

3. A carbon electrode for are lamps, comprising a body of carbon, acore, a radially projecting external rib and a longitudinal metallicconductor embedded in the rib.

4. A carbon electrode for are lamps, having a radially projectingexternal rib, and a longitudinal metallic conductor embedded in the rib.

5. A cored electrode for electric arc lamps, having its body port-ionprovided with an external serrated rib, said electrode also providedwith a longitudinal metallic conductor which is arranged between thecore and the serrated edge of the rib.

In testimony whereof I ailix my signature in presence of two witnesses.

JO-SEF H. HALLBERG.

lVit-nesses STEPHEN S. NEWTON, 7M. R. BAIRD.

